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1

Increased nitrous oxide emissions resulting from nitrogen addition and increased precipitation in an alpine meadow ecosystem

100%
Du Y., Guo X., Cao G., Li Y.
Polish Journal of Environmental Studies
|
2016
|
tom 25
|
nr 1
The effects of nitrogen (N) addition and increased precipitation on nitrous oxide (N2O) emissions in alpine meadow ecosystems are still unclear. In this study, we measured N2O fluxes on the Tibetan plateau under interactions of moderate atmospheric N deposition and increased precipitation using a closed chamber method. Under all applied treatment conditions, the alpine meadow ecosystem acted as a source of N2O. The N2O emission rate reached a maximum of 74.83±14.40 μg m-2 h-1, with a significant increase in emission rate of 68.76% following N addition when compared with the control plot (p<0.05). Increased precipitation, and its interactive combination with N deposition, enhanced the N2O emission rate by 53.90% and 44.52%, respectively. However, there was no significant difference between these two treatments. Increased precipitation would help to mitigate N2O fluxes under global nitrogen deposition conditions.
2

Experimental anti-GBM nephritis as an analytical tool for studying spontaneous lupus nephritis

100%
Du Y., Fu Y., Mohan C.
Archivum Immunologiae et Therapiae Experimentalis
|
2008
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tom 56
|
nr 1
3

The impact of plateau zokor Myospalax fontanierii burrows on alpine meadow vegetation on the Qinghai-Xizang (Tibetan) plateau

100%
Zhang Y., Liu J., Du Y.
Acta Theriologica
|
2004
|
tom 49
|
nr 1
The impact of burrows constructed by plateau zokors Myospalax fontanierii (Milne- -Edwards, 1867) on alpine meadow vegetation on the Qinghai-Xizang (Tibetan) plateau was investigated. Plant samples taken from quadrats directly over active zokor burrows, back-filled burrows, adjacent burrow controls, and random sites from a field, in which no burrows or mounds occurred were compared. The biomass of plants (below- and above-ground) directly over shallow active burrows was significantly lower than on control plots. This reduction in biomass was not significantly different than that between deep active burrows and control plots. There were no significant differences between above- and below-ground plant biomass on areas perpendicular to active burrows when compared to random sites. Back-filling soil in burrows could promote the growth of above-ground monocotyledonous plants. However, the burrowing activities of zokors had a negative effect on biomass of dicotyledonous plants.
4

A new genus in the subfamily Phycitinae [Lepidoptera: Pyralidae] from China

100%
Du Y., Sung S., Wu C.
Annales Zoologici
|
2005
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tom 55
|
nr 1
A new genus, Furcata is erected and Furcata quadrangula is described as a new species Jour known species, Furcata dichromella (Ragonot), F. paradichromella (Yamanaka) F.pseudodichromella (Yamanaka) and F. karenkolla (Shibuya) are positioned in the new genus with F. dichromella (Ragonot) as the type species. The first three are transferred from Trachycera Ragonot, the last from Eurhodope Hübner. Both male and female genitalia of these five species, except the female of the new species, are illustrated. The type of the new species and other specimens examined are deposited in the Institute of Zoology, Chinese Academy of Sciences, Beijing (abbreviated as IZCAS in the following text).
5

ZNF750 inhibits the proliferation and invasion of melanoma cells through modulating the Wnt/beta-catenin signaling pathway

88%
Du Y., LV G., Jing C., Liu J., Liu J.
Folia Histochemica et Cytobiologica
|
2020
|
tom 58
|
nr 4
6

Simulating N2O emission from Kobresia humilis Serg. alpine meadow on Tibetan Plateau with the DNDC model

88%
Du Y., Cui X., Cao G., Zhao X., Yang G.
Polish Journal of Ecology
|
2011
|
tom 59
|
nr 3
Field me asured N2O emissions in two years were used to parameterize and validate a process-based model, DNDC, for an alpine Kobresia humilis meadow on the Tibetan Plateau in China. Although this model failed to capture the N2O fluxes in some time periods in the spring or autumn, the modeled results showed overall a good performance in terms of simulating the seasonal variation of N2O fluxes and quantifying the annual total emissions. The relative deviation on the annual basis was about 12.4% and –15.9% for the two years, respectively. The modeled data showed that nitrification contributed about 53% of total N2O production, slightly higher than denitrification. The modeled fluxes were sensitive to soil organic content (SOC), pH, and temperature, but less sensitive to variation of precipitation, soil ammonium and nitrate contents. Further mo difications for the model were suggested to focus on the process of soil freezing and thawing as well as the crop growth sub-model that would improve the model’s performance for quantifying N2O emission from the alpine meadow.
7

Effect of grazing intensity on soil and plant δ15N of an alpine meadow

88%
Du Y., Guo X., Zhou G., Cao G., Li Y.
Polish Journal of Environmental Studies
|
2017
|
tom 26
|
nr 3
The mechanisms underlying the retention of inorganic N were still not well understood in an alpine meadow on the Tibetan Plateau as well as in other high-altitude meadow sites greatly grazed and disturbed. We conducted field soil and dominant species foliar nitrogen natural abundance of stable isotope ratios (δ¹⁵N) under four grazing intensities. It was demonstrated that soil δ¹⁵N decreased significantly from 5.83±0.20‰ to 2.17±0.48‰ at 0-10 cm with the elevation of grazing intensity. Grazing reduced the degree of ecosystem N openness. The δ¹⁵N value of surface soil was mainly affected by soil total nitrogen. Furthermore, the degree of nitrogen limitation increased with grazing elevation for sedge family and Gramineae family plants.
8

Contribution of the vegetation layers in the nitrous oxide emission from Alpine Kobresia humulis Serg. meadow ecosystem on the Tibetan Plateau

88%
Du Y., Cao G., Deng Y., Sun G., Cui X.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 1
Nitrous oxide (N₂O) was one of the major atmospheric greenhouse gases. Its budget was poorly understood in alpine meadow, a dominant vegetation type on the Tibetan Plateau. To characterize a Kobresia humilis meadow on the plateau, N₂O emission rates were monitored from June 2003 to June 2006 in the study area located at 3280 m a.s.l. Nine plots with 1 m × 1 m each were divided into three treatments, i.e. intact herbaceous community (HCK), removal of aboveground plant biomass (CBK), and removal of both above and belowground plant biomass (BSK), to estimate contribution of plants, r hizosphere and bulk soil to the total N₂O emission. N₂O emission from plant aboveground biomass was calculated by flux difference between HCK and CBK, denoted as F (HCK-CBK), from rhizosphere by F (CBK-BSK), and from bulk soil was the flux in BSK treatment. Static chambers (height 50 cm, area 0.5 × 0.5 m²) were used for gas collection. N₂O emission rate was significantly correlated with soil temperature at 5 cm depth in both HCK and BSK (P <0.001). Both treatments demonstrated a seasonal peak rate in growing season and minimum rate in dormancy period. The mean emission rates in the three years were 39.7±2.9 and 30.6±2.5 μg m⁻² h⁻¹ in HCK and BSK, respectively, with the former significantly higher than the latter (P <0.05). In CBK, however, the emission rate did not show consistent correlation with soil temperature, especially in growing season. Its three-year mean emission rate was 36.2±3.3 μg m⁻² h⁻¹. In the K. humilis meadow, bulk soil contributed much more than plants and rhizosphere. The mean emission rate was 3.5±2.9, 5.7±3.8, and 30.6±2.5 μg m⁻² h⁻¹ (P <0.001) from plants, rhizosphere and bulk soil, and these accounted for 9, 14 and 77%, separately. Our results implied that N₂O emission rate decreased little with grazing as indicated by the difference between HCK and CBK in K. humilis meadow (P <0.05). N₂O emission from alpine meadow could not be ignored in addressing regional greenhouse gases budget on the Tibetan Plateau, considering the vast area and much higher radiative forcing of N₂O.
9

Responses of photosystem II photochemistry and the alternative oxidase pathway to heat stress in grape leaves

76%
Sun Y., Liu X., Zhai H., Gao H., Yao Y., Du Y.
Acta Physiologiae Plantarum
|
2016
|
tom 38
|
nr 10
10

Gaba exist as a negative regulator of cell proliferation in spermaogonial stem cells

76%
Du Y., Du Z., Zheng H., Wang D., Li S., Yan Y., Li Y.
Cellular and Molecular Biology Letters
|
2013
|
tom 18
|
nr 2
γ-amino butyric acid (GABA) is the main inhibitory neurotransmitter in the mammalian central nervous system. GABA is also found in many peripheral tissues, where it has important functions during development. Here, we identified the existence of the GABA system in spermatogonial stem cells (SSCs) and found that GABA negatively regulates SSC proliferation. First, we demonstrated that GABA and its synthesizing enzymes were abundant in the testes 6 days postpartum (dpp), suggesting that GABA signaling regulates SSCs function in vivo. In order to directly examine the effect of GABA on SSC proliferation, we then established an in vitro culture system for long-term expansion of SSCs. We showed that GABAA receptor subunits, including α1, α5, β1, β2, β3 and γ3, the synthesizing enzyme GAD67, and the transporter GAT-1, are expressed in SSCs. Using phosphorylated histone H3 (pH3) staining, we demonstrated that GABA or the GABAAR-specific agonist muscimol reduced the proliferation of SSCs. This GABA regulation of SSC proliferation was shown to be independent of apoptosis using the TUNEL assay. These results suggest that GABA acts as a negative regulator of SSC proliferation to maintain the homeostasis of spermatogenesis in the testes
11

Effects of different biochars on physicochemical properties and fungal communities of black soil

76%
Du Y., Wu J., Anane P.-S., Wu Y., Wang C., Liu S.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 5
In this study, a combination of indoor culture and high-throughput sequencing was used to analyze changes in nutrients and fungal communities in black soil after the addition of biomass charcoal. The following conclusions were drawn: 1) After six months of constant temperature, black soils containing biomass carbon changed in physicochemical properties. For example, soil pH, organic matter, water content, available phosphorus, and available potassium increased compared with CK treatment (P<0.05). 2) It was observed from high-throughput sequencing that the fungal diversity of black soil also changed. High-throughput sequencing detected five fungal phyla, including Ascomycota, Basidiomycota, Chytridiomycota, Zygomycota, and Aspergillus (Glomeromycota), in which Ascomycota was the predominant group of fungi, which accounted for about 70.6% of the total number of OTUs. The sequencing also detected 67 known genera, among which the dominant genus included the genus Geomyces and sickle Fusarium, Chaetomium, Penicillium, Humicola. The analysis of fungal diversity concluded that the abundance and diversity of fungi in the black soil after adding biomass carbon increased. In the redundancy analysis (RDA), environmental factors had a great influence on the abundance and community composition of fungi. Therefore, adding biomass carbon could not only improve the soil nutrients but also were significant in maintaining the diversity of soil fungal communities.
12

Effects of landuse change on CH4 soil-atmospheric exchange in alpine meadow on the Tibetan Plateau

64%
Guo X., Du Y., Han D., Xu X., Zhang F., Lin L., Li Y., Liu S., Ouyang J., Cao G.
Polish Journal of Environmental Studies
|
2015
|
tom 24
|
nr 4
Degradation of shrub meadows and reclamation of alpine meadows may heavily affect the soil sink for atmospheric methane (CH₄), but this is poorly understood. Therefore, in situ measurements of atmospheric CH₄ consumption were conducted in four landuse types: natural alpine meadow (NM), Elymus nutans pasture (EP), herbaceous meadow in shrub (HS), and a P. fruticosa shrub meadow (PS) within two years. CH₄ fluxes were measured using static chambers and gas chromatography. All four types of land use showed atmospheric CH₄ sink throughout the two years, with mean soil CH₄ consumption rates at 24.6±10.9, 33.8±15.0, 39.8±10.3, and 28.1±12.1 µg CH₄·m⁻²·hr⁻¹ for NM, EP, PS, and HS, respectively. Soil CH₄ consumption increased by 40% by reclamation from NM to EP, while it decreased by 30% by degradation from PS to HS. Soil CH₄ consumption in four types of land use was significantly correlated with temperature at 5 cm depth (P<0.01) and the soil water-filled pore space (WFPS) (P<0.05). Temperature showed stronger effects on soil CH₄ consumption than WFPS, except in NM. UV radiation was positively correlated with soil CH₄ consumption with increasing temperature and decreasing soil moisture. These findings indicate that a decrease in the grazing pressure in shrub meadows and increase in the area of artificial pasture reclaimed from alpine meadows would enhance the CH₄ sink in alpine meadows on the Tibetan Plateau.
13

Aerobic methane emission from plant: comparative study of different communities and plant species of Alpine meadow

64%
Guo X., Du Y., Li J., Liu S., Han D., Li Y., Lin L., Zhang F., Oyang J., Cao G.
Polish Journal of Ecology
|
2015
|
tom 63
|
nr 2
This study was aimed at qualifying the methane emission ability of different communities in alpine meadow, and monitoring if the dominant species from these communities could emit methane in a sand culture experiment. Using the static chamber technique and gas chromatography method, two experiments were conducted in the field and in laboratory. First, the methane flux rate was measured in plant communities: natural alpine meadows (NM), Elymus nutans pasture (EP), herbaceous community in shrub (HS), and a Poa fruticosa meadow (PS). A 3-month sand culture experiment was conducted to show the non-microbial methane emission from living plants. Average methane emission rates were estimated to be 16.83 µg m⁻² h⁻¹(range -49.3–107.8), 28.49 µg m⁻² h⁻¹ (range -55.0–96.2) and 20.91 µg m⁻² h⁻¹ (range -31.9– 145.8) for NM, EP, and PS, respectively. Methane emission rate from EP was significantly higher than from NM during the growing season. The reclaim of grassland would enhance the methane emission in this aera through this one year's measurement, but whether this conclusion suit to the whole Tibet Plateau, it remains further longer time and larger spatial scale experiments to verify it. The result of the sand culture experiment showed that some plant species emitted methane in an aerobic, nonmicrobial environment, most of herbaceous species showed a methane emission characteristic, the methane emission from plant may have a species dependent characteristic.
14

Exogenous ABA induces drought tolerance in upland rice: the role of chloroplast and ABA biosynthesis-related gene expression on photosystem II during PEG stress

64%
Teng K., Li J., Liu L., Han Y., Du Y., Zhang J., Sun H., Zhao Q.
Acta Physiologiae Plantarum
|
2014
|
tom 36
|
nr 08
Abscisic acid (ABA) plays an important role in regulating photosynthesis under stress. To understand the differential function of exogenous ABA in the regulation of drought tolerance between two rice (Oryza sativa L.) genotypes, upland rice (UR, resistant to drought stress) and lowland rice (LR, susceptible to drought stress), photosynthetic parameters, chlorophyll fluorescence parameters, and the expression of chloroplast and ABA biosynthesisrelated genes were investigated under 15 % polyethylene glycol (PEG) and exogenous ABA (60 µM) treatments. In both rice lines, most of the photosynthetic parameters, chlorophyll fluorescence parameters, and chloroplast and ABA biosynthesis-related gene transcript levels were rapidly reduced by PEG stress, with the exception of up-regulated levels of OsPsbA, OsNCED3, OsNCED4, and OsZEP in LR and OsNCED3, OsNCED4, and OsZEP in UR. Moreover, a rapid stress-responsive regulation mechanism was found in UR according to the more rapid and strong up-regulation of three ABA biosynthesis-related genes in UR than in LR. Under PEG stress, exogenous ABA application significantly enhanced the recovery of the net photosynthetic rate (Pₙ), stomatal conductance (Gₛ), and transpiration rate (Tᵣ) in UR, with increased expression of OsPsbD1, OsPsbD2, OsNCED2, OsNCED3, OsNCED4, and OsNCED5. These data suggest a role for chloroplast and ABA biosynthesis-related genes in photosystem II (PSII) induction by exogenous ABA in the UR genetic background.
15

Effects of increased precipitation and nitrogen deposition on methane uptake of Alpine meadow in Qinghai-Tibet Plateau: in situ experiments

52%
Guo X., Dail L., Zhang F., Li Y., Lin L., Li Q., Dawen Q., Fan B., Ke X., Cao G., Zhou H., Du Y.
Polish Journal of Ecology
|
2020
|
tom 68
|
nr 2
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